Count edge with NI 9401

[Yves]

Hi,

I want to count edges with the NI-9401 module. I have tried to do it with a vi like the "Count Digital Events-Buffered -Ext-Clk.vi".
But with this vi I can't select the correct channel.
What's wrong with this vi? Is there another solution?

Thanks for any help

Yves

[andre.buurman@carya]

Have you read this manual?

It tells you step by step how to go about programming a cRIO system, it involves something more than a daq card.


Message Edited by andre.buurman@carya on 12-11-2007 03:36 PM

[MarkGrot]

Andre is correct that it is a bit more complicated if you are using Compact RIO.

If you are using your NI 9401 in a CompactDAQ chassis, make sure you have the module in slot 5 or 6.  The slot number you use doesn't matter for analog input or output, but it does for digital tasks.  You can do correlated digital in slots 1-4, PFI/counter tasks in slots 5-6, and software timed digital in all 8 slots.

[Matthieu Papaux]

Hi,

If you are using cDAQ, Mark explain it well.
You can also use Measurement and Automation Explorer to test it (Test Panel).
There is also a great example to do that: Count Digital Events.vi

If you are using cRIO, you can check this example:
Counters - Rseries.vi and use the high Speed I/O on the FPGA to create a counter.

Regards.

Matthieu

National Instruments Switzerland